Characteristic Generators and Dualization for Tail-Biting Trellises

This paper focuses on dualizing tail-biting trellises, particularly KV-trellises. These trellises are based on characteristic generators, as introduced by Koetter/Vardy (2003), and may be regarded as a natural generalization of minimal conventional trellises, even though they are not necessarily minimal. Two dualization techniques will be investigated: the local dualization, introduced by Forney (2001) for general normal graphs, and a linear algebra based dualization tailored to the specific class of tail-biting BCJR-trellises, introduced by Nori/Shankar (2006). It turns out that, in general, the BCJR-dual is a subtrellis of the local dual, while for KV-trellises these two coincide. Furthermore, making use of both the BCJR-construction and the local dualization, it will be shown that for each complete set of characteristic generators of a code there exists a complete set of characteristic generators of the dual code such that their resulting KV-trellises are dual to each other if paired suitably. This proves a stronger version of a conjecture formulated by Koetter/Vardy.Comment: 26 page

Time-ordering Dependence of Measurements in Teleportation

We trace back the phenomenon of "delayed-choice entanglement swapping" as it was realized in a recent experiment to the commutativity of the projection operators that are involved in the corresponding measurement process. We also propose an experimental set-up which depends on the order of successive measurements corresponding to noncommutative projection operators. In this case entanglement swapping is used to teleport a quantum state from Alice to Bob, where Bob has now the possibility to examine the noncommutativity within the quantum history.Comment: 20 pages, 7 figures; v2; formalism of isometries elaborately discussed, some changes in formulas, figure and reference added; typos correcte

SRA: Fast Removal of General Multipath for ToF Sensors

A major issue with Time of Flight sensors is the presence of multipath interference. We present Sparse Reflections Analysis (SRA), an algorithm for removing this interference which has two main advantages. First, it allows for very general forms of multipath, including interference with three or more paths, diffuse multipath resulting from Lambertian surfaces, and combinations thereof. SRA removes this general multipath with robust techniques based on $L_1$ optimization. Second, due to a novel dimension reduction, we are able to produce a very fast version of SRA, which is able to run at frame rate. Experimental results on both synthetic data with ground truth, as well as real images of challenging scenes, validate the approach

De dokter, het leven en de dood

De dood laat niet met zich sollen. Maar daar waar de dokter uit het sprookje van het begin zich moest behelpen met een kruidendrankje en de influisteringen van zijn bijzondere oom, stel ik vast dat onze dood inmiddels behoorlijk maakbaar en redelijk bespreekbaar is geworden. Dat is de basis voor voortgaande gedachtevorming, discussie, onderzoek en verbetering van de praktijk. Er zijn bijvoorbeeld duidelijke aanwijzingen dat er nog teveel bewuste en onbewuste onbekwaamheid en onhandigheid is bij zorgverleners, en dat er nog teveel onzekerheid en onvervulde behoeften zijn bij patiënten en hun familie. Bovendien is er nog onvoldoende kennis over de omvang, aard, oorzaken en gevolgen van passende en niet-passende zorg in de laatste levensfase. En het is een cliché, maar we gaan maar één keer dood, dus het kan niet over als het niet goed is gegaan. Onderzoek heeft al veel aanknopingspunten voor verbetering opgeleverd, zowel wat betreft adequate behandeling van symptomen als wat betreft methoden voor goede besluitvorming en communicatie. Onze eigen, veelal in samenwerking lopende projecten op het gebied van palliatieve sedatie, medicatiegebruik, zorg in het ziekenhuis en de bijdrage van consultatieteams, ook wat kostenbesparingen betreft, communicatie en besluitvorming, prognostiek, en zorg in de stervensfase zullen verder bijdragen aan onze kennis op dit gebied. We sluiten daarmee graag aan bij een van de strategische doelstellingen van het Erasmus MC, ‘zichtbaar betere zorg’, niet alleen door sterftecijfers zo laag mogelijk te houden en daardoor als ziekenhuis hoog op ranglijstjes terecht te komen, maar ook door passende zorg te bieden als het overlijden onvermijdelijk is geworden. Ook door de verdere ontwikkeling van onderwijs voor geneeskundestudenten en post-academisch onderwijs voor artsen en onderzoekers wil ik daar graag mijn bijdrage aan leveren

Current driven switching of magnetic layers

The switching of magnetic layers is studied under the action of a spin current in a ferromagnetic metal/non-magnetic metal/ferromagnetic metal spin valve. We find that the main contribution to the switching comes from the non-equilibrium exchange interaction between the ferromagnetic layers. This interaction defines the magnetic configuration of the layers with minimum energy and establishes the threshold for a critical switching current. Depending on the direction of the critical current, the interaction changes sign and a given magnetic configuration becomes unstable. To model the time dependence of the switching process, we derive a set of coupled Landau-Lifshitz equations for the ferromagnetic layers. Higher order terms in the non-equilibrium exchange coupling allow the system to evolve to its steady-state configuration.Comment: 8 pages, 2 figure. Submitted to Phys. Rev.

Transmission needs across a fully renewable European power system

The residual load and excess power generation of 27 European countries with a 100% penetration of variable renewable energy sources are explored in order to quantify the benefit of power transmission between countries. Estimates are based on extensive weather data, which allows for modelling of hourly mismatches between the demand and renewable generation from wind and solar photovoltaics. For separated countries, balancing is required to cover around 24% of the total annual energy consumption. This number can be reduced down to 15% once all countries are networked together with uncon- strained interconnectors. The reduction represents the maximum possible benefit of transmission for the countries. The total Net Transfer Capacity of the unconstrained interconnectors is roughly twelve times larger than current values. However, constrained interconnector capacities six times larger than the current values are found to provide 97% of the maximum possible benefit of cooperation. This motivates a detailed investigation of several constrained transmission capacity layouts to determine the export and import capabilities of countries participating in a fully renewable European electricity system

Mechanisms of spin-polarized current-driven magnetization switching

The mechanisms of the magnetization switching of magnetic multilayers driven by a current are studied by including exchange interaction between local moments and spin accumulation of conduction electrons. It is found that this exchange interaction leads to two additional terms in the Landau-Lifshitz-Gilbert equation: an effective field and a spin torque. Both terms are proportional to the transverse spin accumulation and have comparable magnitudes

News media coverage of euthanasia: A content analysis of Dutch national newspapers

© 2013 Rietjens et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0),which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background: The Netherlands is one of the few countries where euthanasia is legal under strict conditions. This study investigates whether Dutch newspaper articles use the term ‘euthanasia’ according to the legal definition and determines what arguments for and against euthanasia they contain. Methods: We did an electronic search of seven Dutch national newspapers between January 2009 and May 2010 and conducted a content analysis. Results: Of the 284 articles containing the term ‘euthanasia’, 24% referred to practices outside the scope of the law, mostly relating to the forgoing of life-prolonging treatments and assistance in suicide by others than physicians. Of the articles with euthanasia as the main topic, 36% described euthanasia in the context of a terminally ill patient, 24% for older persons, 16% for persons with dementia, and 9% for persons with a psychiatric disorder. The most frequent arguments for euthanasia included the importance of self-determination and the fact that euthanasia contributes to a good death. The most frequent arguments opposing euthanasia were that suffering should instead be alleviated by better care, that providing euthanasia can be disturbing, and that society should protect the vulnerable. Conclusions: Of the newspaper articles, 24% uses the term ‘euthanasia’ for practices that are outside the scope of the euthanasia law. Typically, the more unusual cases are discussed. This might lead to misunderstandings between citizens and physicians. Despite the Dutch legalisation of euthanasia, the debate about its acceptability and boundaries is ongoing and both sides of the debate are clearly represented

How Do You Build a "Culture of Health"? A Critical Analysis of Challenges and Opportunities from Medical Anthropology.

The Robert Wood Johnson Foundation's Culture of Health Action Framework aims to "make health a shared value" and improve population health equity through widespread culture change. The authors draw upon their expertise as anthropologists to identify 3 challenges that they believe must be addressed in order to effectively achieve the health equity and population health improvement goals of the Culture of Health initiative: clarifying and demystifying the concept of "culture," contextualizing "community" within networks of power and inequality, and confronting the crises of trust and solidarity in the contemporary United States. The authors suggest that those who seek to build a "Culture of Health" refine their understanding of how "culture" is experienced, advocate for policies and practices that break down unhealthy consolidations of power, and innovate solutions to building consensus in a divided nation